Educator

How Nerves Work

• The differences in ion distribution across a membrane results in a voltage difference (or potential) across the membranes of all cells.

• The sodium/potassium pumps and the differential permeabilities of ion channels in the membrane create a concentration of sodium ions that is higher on the outside of the membrane and a concentration of potassium ions that is higher on the inside of the membrane.

• Some signals can produce ion flow changes in a neuron. In this Lesson, you’ll learn about a unique feature of neurons, called the action potential, that results from ion flow changes.

• Action potentials cause the release of chemical messengers from the neurons. Nerve gases and many drugs interfere with these chemical messengers.